Info needed with my 71 Mach1

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A good source for casting and date code info is this website, www.mustangtek.com  I have found it pretty reliable, but like all, not 100% correct.

On my engine, the heads are D1AE-GA. Date code is 0M01 (not 04 as previously mentioned). They are 4 dot (4*) listed as 71 351C Mustang / Torino, 4V with 2.19" intake, 1.71" exhaust, 64cc closed chamber, in port 2.5" x 1.75", ex port 2.00" x 1.74" It shows a Ford number as D1AZ-6049-B, not sure if that is correct though.

If you can, please list your intake ID info as it all helps.

What Holley carb is fitted and dose it have a factory distributor, points or upgrade to electronic. This is for future help we all know you're going to need.

These can be fun or frustrating for sure, so enjoy your new toy.

Geoff.
I will dig deeper into this, are there any members here with a 71 Q code? What’s the best octane to run this at so it won’t ping. Do you use a octane additive, if so what brand. Thanks

 
A good source for casting and date code info is this website, www.mustangtek.com  I have found it pretty reliable, but like all, not 100% correct.

On my engine, the heads are D1AE-GA. Date code is 0M01 (not 04 as previously mentioned). They are 4 dot (4*) listed as 71 351C Mustang / Torino, 4V with 2.19" intake, 1.71" exhaust, 64cc closed chamber, in port 2.5" x 1.75", ex port 2.00" x 1.74" It shows a Ford number as D1AZ-6049-B, not sure if that is correct though.

If you can, please list your intake ID info as it all helps.

What Holley carb is fitted and dose it have a factory distributor, points or upgrade to electronic. This is for future help we all know you're going to need.

These can be fun or frustrating for sure, so enjoy your new toy.

Geoff.
I will dig deeper into this, are there any members here with a 71 Q code? What’s the best octane to run this at so it won’t ping. Do you use a octane additive, if so what brand. Thanks
 "are there any numbers here with a Q code" ? Not sure what you mean, but yes. As far as I know, all 351C engines are stamped with a partial VIN on the left bank under the head. They can be hard to read and you may need to remove some paint to see it.

All the rest is getting into a lot of detailed info, so for now please address one subject at a time so people like me don't get confused!! That's not hard to do these days.

I'll be back on this later. I'm headed out to see "Ford V Ferrari"

Geoff.

 
Sorry about that, what I was trying to say is did ford have the Q code put on the vin tags for the CJ motors in 1971. 2nd, are there any members here with that Q code in there vin. Again, sorry about that. I think 1000 times faster than I can type.

 
Because the Q code has open chambers and lower compression 89 octane pump gas should be fine with no additives. My M code runs fine on 91 octane with no additives.

This is assuming your heads aren't all carboned up.

 
There were very few Q codes produced in 71. There would be a Q in the vin. But like others have said best thing is to pull valve covers and check your numbers. I have a Q code car, but it’s a 72 so no help. I did just put some 71 closed chamber heads on the engine though and what a difference.

 
Sorry about that, what I was trying to say is did ford have the Q code put on the vin tags for the CJ motors in 1971. 2nd, are there any members here with that Q code in there vin. Again, sorry about that. I think 1000 times faster than I can type.
 The VIN would read something like 1f05Q if it ever existed, which I don't think it did, but I'm not the expert on when exactly Ford switched from M to Q.

As you have, or believe you have, an M code, 1f05MXXXXXX, why the concern about the Q code motor? Another tell tale is the intake manifold. The Q code, aka CJ, will have a spread bore manifold whereas the M code with no fancy name, is a square bore, i.e. the 4 bore holes are all the same size. There are many members here with Q code motors, 2f05QXXXXXX. Some Mustangs were built in Metuchen and the VIN id would be 1t05M, but they only built them there for 1 year, 1971.

A good book to have on hand is "The Mustang and Cougar Tagbook (1965-1973 models) by Kevin Marti. You can buy it from most vendors like NPD or from Marti Auto Works. Well worth buying.

 
I will go and buy that book. Thanks for the info. I think I have the M code engine. I have the original distributor and it has single point not duel point. From what I see both engines have there good points about them. Over the holidays I will dig much deeper. Thanks again

 
I believe the Q codes started showing up in May '71, and most (all) were probably in California. I believe M codes continued to be sold until the end of the model year. One "Mustang" web site says that the M codes changed to CJs in May '71 and the CJs were also called M codes, they don't even know that there is/was a Q code. So, I can see why the confusion keeps going. Maybe someone with the Marti book can look up the production numbers of the engines. I looked online, but the only break-out I could find is by body style.

 
I will go and buy that book. Thanks for the info. I think I have the M code engine. I have the original distributor and it has single point not duel point. From what I see both engines have there good points about them. Over the holidays I will dig much deeper. Thanks again
 It's a very interesting book.

 As Don say in his reply, lots of confusion.

On the 72 Q code I owned it only had a single point distributor, but then again and I only found this out for sure 3 or 4 years back, the block was a Boss, so anything could and probably was changed by the PO. Personally, I thought it was only R code motors that got dual point Dizzy's ( R code 71 Boss 351C and 72 HO) I did find a dual point Windsor distributor at a swap meet earlier this year, so yes they could have been on 72 CJ's, anything is possible where Ford are concerned.

Geoff.

 
I believe the Q codes started showing up in May '71, and most (all) were probably in California. I believe M codes continued to be sold until the end of the model year. One "Mustang" web site says that the M codes changed to CJs in May '71 and the CJs were also called M codes, they don't even know that there is/was a Q code. So, I can see why the confusion keeps going. Maybe someone with the Marti book can look up the production numbers of the engines. I looked online, but the only break-out I could find is by body style.
We must of read the same articles. It makes sense ford would use up all its existing parts first then switch over to the new parts. Hence the confusion. The May change was supposed to be for the tighter emissions standards.

 
I believe the Q codes started showing up in May '71, and most (all) were probably in California. I believe M codes continued to be sold until the end of the model year. One "Mustang" web site says that the M codes changed to CJs in May '71 and the CJs were also called M codes, they don't even know that there is/was a Q code. So, I can see why the confusion keeps going. Maybe someone with the Marti book can look up the production numbers of the engines. I looked online, but the only break-out I could find is by body style.
I seem to recall something like 144 Q codes were made in 71. I believe our resident Ford guru Secluff has posted on this previously.

 
I will go and buy that book. Thanks for the info. I think I have the M code engine. I have the original distributor and it has single point not duel point. From what I see both engines have there good points about them. Over the holidays I will dig much deeper. Thanks again
 It's a very interesting book.

 As Don say in his reply, lots of confusion.

On the 72 Q code I owned it only had a single point distributor, but then again and I only found this out for sure 3 or 4 years back, the block was a Boss, so anything could and probably was changed by the PO. Personally, I thought it was only R code motors that got dual point Dizzy's ( R code 71 Boss 351C and 72 HO) I did find a dual point Windsor distributor at a swap meet earlier this year, so yes they could have been on 72 CJ's, anything is possible where Ford are concerned.

Geoff.
To top this, my '73 Q-code came with a double-dizzy from the factory. But instead of the overall thought it came with no 4-bolt mains on the original q-code block. Why? I don't know... It is an April 1973 car.

 
I will go and buy that book. Thanks for the info. I think I have the M code engine. I have the original distributor and it has single point not duel point. From what I see both engines have there good points about them. Over the holidays I will dig much deeper. Thanks again
 It's a very interesting book.

 As Don say in his reply, lots of confusion.

On the 72 Q code I owned it only had a single point distributor, but then again and I only found this out for sure 3 or 4 years back, the block was a Boss, so anything could and probably was changed by the PO. Personally, I thought it was only R code motors that got dual point Dizzy's ( R code 71 Boss 351C and 72 HO) I did find a dual point Windsor distributor at a swap meet earlier this year, so yes they could have been on 72 CJ's, anything is possible where Ford are concerned.

Geoff.
To top this, my '73 Q-code came with a double-dizzy from the factory. But instead of the overall thought it came with no 4-bolt mains on the original q-code block. Why? I don't know... It is an April 1973 car.
 Tim, I learn something new every day, especially on the dual point dizzy for 72-73 CJ's. As for 4 bolt mains, I have a 'theory' on that. We all know that the block casting were designed to take either 2 or 4 bolt mains, so my 'theory' is Ford had produced far more 4 bolt caps than needed due to the demise of the Muscle car era. So instead of scrapping them, they simply switch in 1 more operation to drill and tap the blocks for 4 bolt. They also would have used up whatever 2 bolt caps they had on hand, hence, the one you had. Simply put, it was the 'bean counters' at work. OR, perhaps Ford engineers really did find that 4 bolts were better than 2 bolt on any 351C. I sure would like to have them on my M code. Who knows what they were really thinking! 

Geoff.

 
I will go and buy that book. Thanks for the info. I think I have the M code engine. I have the original distributor and it has single point not duel point. From what I see both engines have there good points about them. Over the holidays I will dig much deeper. Thanks again
 It's a very interesting book.

 As Don say in his reply, lots of confusion.

On the 72 Q code I owned it only had a single point distributor, but then again and I only found this out for sure 3 or 4 years back, the block was a Boss, so anything could and probably was changed by the PO. Personally, I thought it was only R code motors that got dual point Dizzy's ( R code 71 Boss 351C and 72 HO) I did find a dual point Windsor distributor at a swap meet earlier this year, so yes they could have been on 72 CJ's, anything is possible where Ford are concerned.

Geoff.
To top this, my '73 Q-code came with a double-dizzy from the factory. But instead of the overall thought it came with no 4-bolt mains on the original q-code block. Why? I don't know... It is an April 1973 car.
I have never seen a Q code that did not have dual point distributor. I complained about the performance of mine when new and dealer installed a dual point centrifugal advance dist. The vacuum can is still there to index the cap but the arm on the diaphragm is cut off. The center shaft had to change and cam is different also. On the two bolt being in there if the VIN# is stamped in the block I would say original but if not replacement.

 My 73 Mach 1 came with the wrong rear end in it broke 3 times before they figured it out. They use what they have to keep the line going. The called and wanted to switch mine to automatic and I would not let them.

 
So, one of the best things I've bought in the past few years is an inspection scope. I have a Ryobi Phone Works scope that uses Bluetooth or WiFi or unicorn antennas or something to connect to my phone. It works okay, but tend to lose connection.

However, Ryobi does make one for their Tek4 line and it has it's own screen.

Ryobi Tek4 Digital inspection scope

There are other manufacturers, but these two I have actually used.

The whole point of this is that if you check the size and length of the lens, they will often fit inside a sparkplug hole...I have used mine to inspect the bores of engines without having to remove the heads. Like, you know, if you wanted to see if you have closed or open chamber heads...or get a look at the vin number stamped on the back of the block...or see some casting dates somewhere you can't get your fingers, much less an eyeball.

 
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